Press die clamping apparatus



V. GEORGEFF' PRESS DIE CLAMPING APPARATUS Original Filed Jan. 16, 1958April 13, 1965 INVENTOR.

VASH. GEQRGEFF BY ATTORNEYS 3,177,698 PRESS DIE CLAMPEJG APPARATUS VasilGeorgetf, La Grange Park, 111., assignor to Daniy Machine Specialties,Inc, Chicago, 111., a corporation of Illinois Original application Jan.16, 1958, Ser. No. 709,324, now Patent No. 3,111,?100, dated Nov. '19,1964. Divided andthis application Aug. 21, 1961, Ser. No. 133,545

5 Claims. (Cl. 72-462) This application is a division of my copendingapplication, Serial No. 709,324, filed January 16, 1958, now US. PatentNo. 3,111,100, granted November 19, 1964, for Quick Die Change Press,which is a continuation-in-part of my copending application, Serial No.604,437, filed August 16, 1956, which issued as US. Patent No. 2,996,-025 for a Readily Changeable Die Assembly for Power Presses.

My invention relates to a quick die change press and more particularlyto a power press having means for changing the press dies in a rapid,convenient, and expeditious manner.

In operation of a power press, one of the most difficult andtime-consuming operations which must be performed is changing the presssetup when a new part is to be produced on the press. In the course ofthis changeover, the old dies must be removed from the press and the newdies must be located accurately on the press bed to permit the upper dieto be secured to the press slide and to permit the lower die to besecured to the press bed. The labor cost of this operation is high,owing to the high hourly wage rate of skilled die setters. Because ofthis high cost of changing the press dies, manufacturers make large runsof one part before changing the setup of a press. While this expedientreduces changeover labor costs, it introduces the necessity of storingand handling a very large number of parts. imbalances in themanufacturers inventory result. In the manufacture of consumer goodsfrequent model changes render obsolete many of the parts previously run,resulting in loss to the manufacturer.

In recent years the metal stamping industry has greatly increased theproduction rate of presses for producing large stampings. Modern pressesare capable of higher over-all speeds with very little correspondingincrease in the drawing speeds. In other words, the over-all press speedhas been increased without exceeding the critical drawing speed of themetal being worked on. The increased production possible on modernpresses has created new problems in manufacturing plants. In order tomaintain steady employment, production in many instances must becontrolled by the number or lengths of theworking shifts. If longproduction runs are made, the storage and handling problems referred tohereinabove arise. If relatively short runs are made to maintain thestorage of piece parts at normal levels, much production time is lostbecause of the diiiiculty of changing dies for each new production. run.An obvious solution to the problems outlined hereinabove is theprovision of a large number of presses, each using a dilferent set ofdies. This solution clearly is an uneconomical one.

Modern presses employ automatic handling equipment for feeding thematerial to be worked on into the press. In order to change the pressdies in the prior art, much of this equipment must be moved to permitremoval of the old dies and insertion of the new dies into the press.Each die change usually requires different mechanical handlingequipment. i

It has been suggested in the prior art that the dies to be assembled onthe press be nested and placed on tracks which are run into the pressbed to permit the dies to be secured to the press slide and bed. Such asystem has not been practical in the prior art, owing to the diflicultyof United States Patent 0 3,177,698 Patented Apr. 13, 1965 ice locatingthe dies properly and to the difficulty of securing the dies to thepress bed and to the press slide. The difli= culty of securing a die tothe press drawing slide is par= ticularly evident in a press in whichthe drawing slide is mounted within a blank holder slide. 1

Another suggestion which has been advanced in the prior art isthe'provision of a deformable upper die carried by the press workingslide and lower dies which are run into the press and secured to thepress bed for cooperation with the deformable upper die. A system ofthis nature not only has the inherent disadvantage outlined hereinaboveof not locating the lower die: properly on the press bed but iscompletely impractical for the formation of large stampings from sheetsteel and similar materials.

I have invented a quick die change press which permits the dies of apress to be changed in a rapid, convenient and expeditious manner. Mypress includes means for accurately positioning the dies run into thepress to permit the dies to be secured respectively to the press innerslide and to the press bed. I provide my assembly with means for rapidlyand expeditiously securing the dies to the press bed and to the pressslide. My press permits the dies to be changed without the excessivelyhigh labor cost i11- curred in changing the dies in presses of the priorart. While, in the prior art, a change in the dies usedon a pressrequires a minimum of two hours time, my press permits a change to bemade in five minutes. In the prior art, for example, for a work week of120 hours in which five die changes are made only eighty hours is actualproduction time, while forty hours time is required to change the diesetup. With my quick die change press for a work week of 120 hours inwhich ten die changes are made, actual production time is 115 hours,while the die setup time required is only live hours. It will be seenthat for twice the number of die changes production time on my press isincreased by thirty-five hours or a percentage increase of 43 /z%.Further, my press results in a corresponding increase in time availablefor die tryout.

My quick die change press has the further advantage that it eliminatesthe need for excess press and plant capacity required for die tryout inbringing out new models. My press maintains very nearly the sameefiiciency of equipment utilization for short-run production as forlongrun production. My presspermits the use of improved handlingequipment over that used in the prior art. This mechanical handlingequipment need not be removed while dies are being set up. In the eventof a breakdown on the press, the die in the press can readily be removedfor repairs, and'the press can be put back into production quickly. Withmy press a die change may be made during a working shift or whenever therequired production quantity of the article produced by the dies beingused has been reached.

One object of my invention is to provide a press die clamping apparatuswhich permits an upper die to be secured to the inner slide in a rapidand expeditious manner.

Another object of my invention is to provide a press die clampingapparatus which permits a press die to be secured to the inner slideWithout the necessity of inserting a tool through the blank holderslide. 1

Other and further objects of my invention will appear from the followingdescription.

In general my invention contemplates the provision of a quick die changepress having a frame and a bed and a drawing slide carried forreciprocation with respect to the bed. My press includes a movablebolster to which I secure the lower die of a pair of dies including anupper die adapted to be secured to the press slide. The frame of mypress has openings through which a pair of dies carried by the bolstermay be moved from. a location adjacent the press to a position over thepress bed. I provide my press with means for accurately positioning thebolster on the drive means for moving respective bolsters carrying pairsof dies and has meansrfor preventing interference between the twobolsters.

In the accompanying drawings which form part of the instantspecification and which are to be read in conjunction therewith and inwhich like reference numerals are used to indicate like parts in thevarious views:

FIGURE 1 is a sectional view of an alternate form of upper dieclamping-means of my quick die change power press.

FIGURE 2 is a plan view of the upper die clamping means of my quickdiechange power press taken along the line 2-2 of FIGURE 1-.

FIGURE 3 is a plan view of the form of my upper die clampingmeans shownin FIGURE 1 taken along the line 3-3 of FIGURE 1.

Referring now to FIGURES 1 to 3, I have shown a form of my clampingmeans which is particularly adapted for use with a press having a blankholder slide. This form of my clamping means obviates the necessity forinserting a tool through the blank holder slide to operate the clampingmeans. In this form of my clamping means 'a motor 164 carried by theinner slide 56 is adapted to be energized to drive a shaft 166 carryingfor rotation with it a pinion 168 disposed in a housing 171?. Pinion1615 engages and drives a gear 172 carried by a hub 174 rotatablysupported on a bushing 176 carried by a shaft 178 supported in housing176. Hub 174 carries a pinion 180 for rotation with the hub, whichpinion 180 engages a gear 182 rotatably supported within the housing 170on thrust bearings 184 and 186; I form a threaded central bore 188 ingear 182. The threads in bore 188 engage threads 191) formed on theshank of a clamping bolt 192. V

The shank of bolt 192 extends downwardly through a bore 194 formed inthe inner slide 56. I form the lower end of bolt 192, as viewed inFIGURE 1, with a head 1% having a generally rectangular cross-sectionalshape. I reduce the other end 1915 of bolt 192 along a diameter to forman end having a generally rectangular cross-sectional area, the majoraxis of which is right angles to the major axis of the cross-sectionalarea of head 1%,

End 198 extends through an opening 200 formed in the top of housing 170and provided with a pair of stops 2%12 and 204. The head 1% is adaptedto pass through a substantially rectangular opening 2% formed in theflange 152 of the upper die at; As will be explained hereinafter, beforethe slide 56 is secured to the die 64, motor 164 has been driven to moveend 1% and head 1% to the brokenline position shown in FIGURES l and 2.In this position of head 19ti its longitudinal axis is parallel to thelongitudinal axis of the cross'section of opening 2% so that as theslide moves down over the upper die, the head 1% moves through opening2%. When the head 1% has thus been moved through'the opening 2%, motor164 is energized to rotate the end 198 to the full-line position shownin FIGURES 1 to 3. When the end 198 has been moved to this position, thelongitudinal axis of head 1% extends at right angles to the longitudinalaxis of the cross section of opening 2%. After end 198 has arrived atthe full-line position in which it is against stops 2112 and 264, uponcontinued rotation of gear 132, bolt 192 is drawn upwardly'to secure theupper die firmly to the slide '56. When the upper die is to be releasedfrom the slide, the direction of rotation of motor 164 is reversed tomove the bolt head and the end 198m the broken-line position Inoperation of my press die clamping means to release die 64 from theinner slide 56 I energize motor 16 1 to drive the bolts 192 to bring theend 1% to the broken-line position against stops 2112 and 264. I11 thisposition of the bolt the inner slide may readily be moved to the top ofits stroke, withdrawing the heads 1% through the openings 2% in theupper die. In operation of my clamping apparatus to secure an upper dieas to the slide 56 I drive the slide 56 downwardly and in the course ofmovement of the inner slide 56 downwardly, the heads 1% are in aposition at which they enter openings 206. With the slide at the bottomof its stroke I energize motor 16 to rotate the bolts first to aposition at which the longitudinal axis of head 15 6 is at right anglesto the longitudinal axis of the cross section of 2%. I continue rotationof the motor until the desired clamping pressure has been reached. I mayaccomplish this, for example, by means of a friction clutch betweenmotor 164 and the gear train for driving the bolts.

It will be seen that I have accomplished the objects of my invention. Ihave provided a quick die change power press which permits the dies of apress to be changed in a simple, rapid and expeditious manner. My presspermits advantage to be taken of the high speed operation of modernpower presses without excessive production time being used for diechanges. My press includes means for accurately locating dies moved intothe press bed in the course of a change in the setup of the press. Mypress includes simple means for securing the upper die to the pressdrawing slide. The arrangement of my press is such that dies may bechanged without disturbing automatic material handling equipment usedwith the press.

It will be understood that certain features and subcombinations are ofutility and may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of myclaims. It is further obvious that various changes may be made indetails within the scope of my claims without departing from the spiritof my invention. It is, therefore, to be understood that my invention isnot to be limited to the specific details shown and described. c

Having thus described my invention, what'I claim is:

1. In a power press having a drawing slide and an upper die to besecured to said slide, a securing assembly including means on one of thedie and slide forming an opening having a major axis and a minor axis, aclamping bolt mounted on the other of said die and slide for movementtherewith and for rotary movement with respect thereto, a head on saidbolt, said head having a cross-sectional area with a major axis and aminor axis, said head being adapted to pass through said opening withthe head and opening major taxes substantially aligned, drive meansadapted to be energized to rotate said bolt, means mounting said drivemeans on said other of said die and said slide for movement therewith,said rotating means being adapted to draw said bolt into the other ofthe die and slide after rotation of the bolt has been arrested.

2. In a power press having a drawing slide andan upper die to be securedto said slide, a securing assembly including means on said. upper. dieforming an opening having a major axis and a minor axis, a clampingbolt' 7 through said opening with the head and opening major axessubstantially aligned, drive means adapted to be energized to rotatesaid bolt, means mounting said drive I means on said slide for movementtherewith, means for limiting the rotation of said bolt when said majoraxes are appreciably out of alignment, said drive means being adapted todraw said bolt into said slide upon continued operation after rotationof said bolt has been arrested.

3. A securing assembly as in claim 2 in which said bolt includes a shankformed with threads, said means for rotating including a gear formedWith a threaded bore, said shank being disposed in said bore.

4. A securing assembly as in claim 2 in which the end of said boltremote from said head is formed with a cross section having a major axissubstantially at right angles to the axis of said head, means forming anopening in which said end is disposed, said opening being formed withstops for limiting the rotation of said bolt.

5. A securing assembly as in claim 2 in which said bolt includes a shankformed with threads, said means for rotating comprising a worm gearformed with a threaded bore, said shank being disposed in said bore, anda Worm for driving said gear.

References Cited by the Examiner UNITED STATES PATENTS CHARLES W.LANHAM, Primary Examiner.

15 NEDWIN BERGER, WILLIAM J.

Machin 292-256.73 Gros 113-33 Cannon 11338 Byerlein 100-295 Lyon 113-49Sugg 1818 Annicq 11349 Sommer et a1 11349 Sommer 100-495 STEPHENSON,

Examiners.

1. IN A POWER PRESS HAVING A DRAWING SLIDE AND AN UPPER DIE TO BESECURED TO SAID SLIDE, A SECURING ASSEMBLY INCLUDING MEANS ON ONE OF THEDIE AND SLIDE FORMING AN OPENING HAVING A MAJOR AXIS AND A MINOR AXIS, ACLAMPING BOLT MOUNTED ON THE OTHER OF SAID DIE AND SLIDE FOR MOVEMENTTHEREWITH AND FOR ROTARY MOVEMENT WITH RESPECT THERETO, A HEAD ON SAIDBOLT, SAID HEAD HAVING A CROSS-SECTIONAL AREA WITH A MAJOR AXIS AND AMINOR AXIS, SAID HEAD BEING ADAPTED TO PASS THROUGH SAID OPENING WITHTHE HEAD AND OPENING MAJOR AXES SUBSTANTIALLY ALIGNED DRIVE MEANSADAPTED TO BE ENERGIZED TO ROTATE SAID BOLT, MEANS MOUNTING SAID DRIVEMEANS ON SAID OTHER OF SAID DIE AND SAID SLIDE FOR MOVEMENT THEREWITH,SAID ROTATING MEANS BEING ADAPTED TO DRAW SAID BOLT INTO THE